nbekenov/circleci-learn

circleci learning path

CircleCI learning path

My work on online cource about CircleCI

• Guidance

• Lesson 1: Creating a simple workflow

  • Principle 1
  • Practice 1
    • Lab 1.1: Setup your first project
    • Lab 1.2: Create jobs and workflow
    • Lab 1.3: Use built-in env variables
    • Lab 1.4: Create env variables
  • Retrospective
    • Question 1
    • Question 2

• Lesson 2: Persisting data in Workflows

  • Principle 1
  • Practice 1
    • Lab 2.1: Cache dependencies
  • Principle 2
  • Practice 2
    • Lab 2.2: Use workspaces
  • Principle 3
  • Practice 3
    • Lab 2.3: Create artifacts
    • Lab 2.4: Save test results
  • Retrospective
    • Question 1

• Lesson 3: Controlling jobs

  • Principle 1
  • Practice 1

• Lesson 4: Manage Secrets

  • Principle 1
  • Practice 1

• Lesson 5: Appendix

  • Principle 1
  • Practice 1

• Further Reading

Guidance

Lesson 1: Creating a simple workflow

Principle 1

TODO: write prefrace Something about CI/CD and CircleCI

Practice 1

Create your first first pipeline in CircleCI that will combine a few simple jobs

Lab 1.1: Setup your first project

• connect github to CircleCI
• create new repo
• create simple config file (.circleci/config.yml)
• use docker image and echo some text
• set working_directory

Lab 1.2: Create jobs and workflow

• create workflow with 3 jobs: test build deploy
• create simple bash script that will echo some text and create file
• add checkout step
• add step where you execute your script

Lab 1.3: Use built-in env variables

• print: workflow id, branch name and number of the build

Lab 1.4: Create env variables

• add an environment variable in project settings
• add a job that will print your environment variable

Retrospective

Question 1:

What is the difference between Organization, Project and Job environment variabls scopes?

Question 2:

Can you use pipeline values outside of job context. Can you use them for example in your shell script?

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Lesson 2: Persisting data in Workflows

Read about persisting data in CircleCI

Principle 1

Caching is particularly useful with package dependency managers Caching persists data between the same job in different Workflow builds.

Practice 1

Lab 2.1: Cache dependencies

• create python virtual environment
• install packages
• Use the save_cache step to cache virtual environment and installed packages
• Use the restore_cache step to restore cached files or directories.

Principle 2

Workspaces persist data between jobs in a single Workflow. Unlike caching, workspaces are not shared between runs as they no longer exists once a workflow is complete.

Practice 2

Lab 2.2: Use workspaces

• 1
• 2

Principle 3

Artifacts persist data after a Workflow has finished.

Practice 3

Lab 2.3: Create artifacts in build job

• 1
• 2

Lab 2.4: Save Test results

• 1
• 2

Further Reading

• https://circleci.com/blog/deep-diving-into-circleci-workspaces/
• https://circleci.com/docs/2.0/configuration-reference/#executors-requires-version-21

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Lesson 3: Controlling jobs

Principle 1

Practice 1

Controlling workflow

Lab 3.1: Execute job only for a specific branch

• create a new branch in your repo
• configure execution of one of the jobs in the workflow to run only when changes pushed only to a new branch
• push your changes at first into main(master) branch - see if the job will run. Then push your changes into new branch and check again

Lab 3.2: Handle failure

• add step that will execute on fail

Lab 3.3: Add approval step

• add approval step between test and deploy jobs

Lab 3.4: Logic statements

Practice 2

Write a reusable command that destroys the stack if deployment failed

Lab 3.4: Use commands to perform rollback

• create a simple CloudFormation template that will create some infrastructure.
• write a job that creates a new stack using template you defined. You can use amazon/aws-cli image
• make your job intentionally fail
• Add a command-step that only executes if the job fails

Lab 3.5: Use orbs

• orbs

Lesson 4: Manage Secrets

Principle 1

• add_ssh_keys option

Lab 4.1:

• Create a key pair
• add contents of PEM file to the SSH keys into CircleCI
• create CFN template that creates EC2 instance. Use your key pair

Principle 2

• add context
• add slack integration

Lesson 5: Appendix

• working with API v2
• personal-api-token
• local CLI
• SSH into your build

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Further Reading

• Using Custom-Built Docker Images
• CircleCI academy
• Convenience images